US 2003917 A
Descripción (El texto procesado por OCR puede contener errores)
June 4, 1935. J, G, BOWDEN 2,003,917
HANDLE GRIP Filed Jan, 24, 1933 Control of a tennis racket,
' practically vpercentage of the players.
give the desired tacky feel, or stituents undergo some change Vably modifies the feel of the grip.
Patented June 4, 1935 i UNITED sTATEs HANDLE GRIP poration of Application Januaryl, 1933,
3 Claims. (C1. 273-75) This invention relates to grips for the handles of tennis rackets, golf clubs, and various other implements and tools, and also to the materials used inmaking such grips. f
golf club, or the like, is lgreatly facilitated if the handle has .the desired feel. Usually this means a certain but very limited degree of tackiness sometimes combined with a slight give or yielding quality. y Naturally the requirements for a grip vary considerably with the nature of the implement on which it is used, and to some extent, also, with the desires of different players. For example, a large proportion of the tennis players prefer to have only a slight degree of tackiness in the racket handle grip, and they want a handle which is very rm, with no give Y or yielding characteristics. Any greatA degree of tackiness interferes with the proper execution of the strokes and slows up the shifting of the racket in the hand which many players make in changing from a fore-hand to a back-hand stroke, or vice versa. Essentially the same qualities are desirable in a squash racket handle, but a greater degree of yield or give is permissible there and is preferred-by alarge proportion of the players. In a golf handle grip more yield is permissible in most cases and a higher degree of tackiness is preferred by many players than would be permissible in a tennis racket grip.
Various kinds of rubber, fabric and leather grips have been proposed to meet these requirements but few of them have gone into use to any substantial extent. As a rule leatherf which has beenimpregnated with oils'and other constituents to give up the desired Vfeel is used most commonly for the handles of golf clubs and squash rackets, while tennis racket handles are generally used bare, no grip having been devised for them which meets'the requirements of any substantial WhileA the leather grip thus is very satisfactory for some purposes, it is open to the objectionthat in a relatively short time it either'losesthe constituents which else these conwhichz undesir- The present invention aims to devise a grip which will meet a wider range of needs than those heretofore available, and which will have a high degree of stability and uniformity.
I have found that an exceptionally satisfactory material for grips can be made by impregnating felt with a suitable rubbery compound serving to bind the fibers of the felt securely together but water, but containing, also, some other ingredients.
permanently bonded to each other by the vulcanized latex rubber left in the goods.
a large measure on desired bonding of the necessary tackiness whileV still retaining the felty Tof all wool felt proximately one-twentieth of an inch thick, very `goed results are obtained by allowing the felt to PATENT OFFICE Boston, Mass., a cor- Serial N0. 653,286
without destroying completely the fibrous or felty feel of the original goods. A particularly satisfactory article can be made by impregnating a sheet of felt with vulcanized rubber latex, drying the goods so impregnated, and then cutting them '5 into strips or other sections suitable for application to a handle. Preferably an all wool felt is used, although other fibers can, if desired, be associated with the wool fibers in very substantial proportions. The best results are produced by 10 using a true felt in which the fibers are" interlocked by a characteristic felting action. vThis necessarily means 'a wool felt but not necessarily anall wool goods. For most purposes a felt having a thickness'of in the neighborhood of one` '15 sixteenth of an inch is satisfactory, although the latex will vreadily penetrate greater thicknesses and the thickness may be determined entirely 'in accordance with the requirements of individual uses.'v No modification of the felt making' Opera- 20 tion is required for this purpose.A The vulcanized latex used may be that readily obtainable on the market as vulcanized latex or that sold under the name of Vultex. Usually these materials contain in the neighborhood of 35% or 40% of rubber 25 dispersed in a natural serum consisting chiefly of Small proportions of protective colloids may be' added to the dispersion in order to prevent coagulation and to give added stability, the latex 30 usually containing also a small proportion of ammonia which acts as a preservative.
When a sheet of felt impregnated in the manner above described'has been dried sufficiently to drive off the water and other volatile constituents 35 of the latex, it will be found that the fibers are At the same time the fibers in the fabric are still prominent and the felty feel ofy the fabric is stillretained to a substantial degree. The extent to which these properties areA affected will depend the proportion of rubber and it is desirable to use a of rubber to produce the fibers and to give the added to the goods, sufiicient proportion appearance and much of the felty structure of the goods. I have found that in treatingA a web seventy-two inches wide and aptake up approximately four-fifths of a gallon of vulcanized latex to the running yard, the latex containing from 35% to 40% of solids. The pro- 55 portion of rubber so added to the goods may, however, be varied within very substantial limits while still producing very satisfactory results.
Various constituents may be added to the latex in order to produce special results. For example, pigments may be added to control the color within reasonable limits. Fillers may be added to control the degree of tackiness, andthe proportion of the dispersing medium naturally will be varied in'accordanceV with the concentration required. In fact, variation of the concentration is a convenient means for controlling the quantity of rubber added to the goods. For some purposes it will be found desirable also to add ladhesives such as casein, glue, or the like, to the latex in order to improve the bond between the latex and fibers as well as of the nished product.
The impregnating operation may be carried out in various ways. i A convenient method consists in running theA goods through an impregnating bathatY such a speed that it can take up the desired quantity of latex, passing the sheet between squeeze rolls to remove the excess material, and then drying ,the impregnated sheet at a moderate heat,.say for example, 150 to 175 F. Usually the surface of the goods is rough and harsh after being dried,vand it can be substantially improved by pressing the dried sheet between plates heated to inthe neighborhood of VF. Often it is more convenient to cut the goods into sheets pressure Aperiod to,
say, one-half br three-quarters of a. minute, but repeating it once or twice until the desired re- The pressing operation removes the surface irregularities, reduces the approximately uniform thickness, and produces a Later the sheetscan be slitted or cut into strips to the rubber art.
vpermanently together with the best results is known as NeKal BX dry sold by the General Dyestu Corporation. My method of procedure has been to run the goods through a bath of this agent, and then, while they are still wet, to run them through the latex bath. The goods could, however, be dried, if desired, between the two baths but this ordinarily is not desirable.
While I have obtained the best results by the use of vulcanized rubber latex, it will be evident that .rubber can be added to the felt in other ways. For example, the felt can be impregnated with ordinary or unvuleanized latex and the rubber subsequently vulcanized at temperatures well below those liable to damage the ber of the fel-t. The so-called cold vulcanizing processes may be used for this purpose and are well known The impregnation may also be produced by dissolving the rubber in a suitable use of volatile solvents also is avoided.
YTypical embodiments of the invention are illustrated in the accompanying drawing in which,
Figure 1 is a plan view of a tennis racket having ,25
a handle provided with a grip portion embodying features of this invention;
Fig. 2 is a perspective view of a strip of felt made in accordance withthis invention; and
Fig. 3 is a perspective view of a small section 0f the stripvshown in Fig. 2 but greatly enlarged.
Figs. 2 and 3 show a. strip 2 of unwovenfeltin which still retains, however, certain of its felty characteristics. Such a strip wound around the handle of a racket is illustrated in Fig. l at 3.
The grip provided by this invention is subaected by any down very uniformly and without changing substantially in characteristics, and is therefore extremely stable. Y Y
Having thus described my invention, YwhatI desire to claim as new is:
l. A handle grip comprising a :flexible strip of col felt, the fibers of which are elastically bonded 2. A handle grip comprising a flexible strip .of woolfeltimpregnated with a suicient proportion of latex rubber to bond` the bers of the felt together,Y the quantity of the rubber being so limited as to preservev a substantial portion of the lfelty feelof the goods. Y
-3. A handle grip comprising a flexible strip of wool felt of `approximately uniform vthickness JAMES G. BOWDEN.